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PC Demolition Lab

General

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The computer that we will be looking at and discussing is the Windows Dell OptiPlex GX280

Before opening the computer we can see

  • Power connector
  • Back pannel connectors
    • USB Ports
    • Video Input
  • Cardslots

After opening the computer the parts that we can initially see are

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  • Motherboard
  • Power Supply
  • Fan
  • Chipsets
  • Ports
  • CD Drive
  • Wires
    • Power Cables
    • Data Cables

The Motherboard

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  • Located in the center of the computer

The motherboard is a large board found in all computers today and allows all of the peripheral drives to communicate via circuts. Circuts (right) are metals which are etched onto a semi conductive board which allows different components of the computer to communicate electrically. Some of the things that are attached to the motherboard and communicate via circuts and connectors are: a power supply, the central processing unit, and the random access memory.


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The motherboard also contains a battery and a crystal. The battery, a panasonic with 3 volts, on the motherboard connects to a chip which controls the time and date even when the computer is not connected to a power source. The crystal (right) is a small piece of quartz inside of a metal container that vibrates and creates electrical signals that can be amplified and used to control the voltage inside of the computer and tells the processor how fast to go, and allows the processor to go faster than energy would alone.




Central Processing Unit

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  • Intel Pentium 4
    • 2 GHz
    • Model- 355895B1
  • San Ace92 Fan
    • Model- 9G0912P2G031
  • Located in CPU socket in the middle of the motherboard.


The processor or the central processing unit (CPU) executes computers instructions by performing arithmetic, using logic gates, and using input/output operations. Most modern day processors are around 2 inches, square and contain many metallic pins on the underside which connect to the motherboard via the processors socket.

Operations are carried out by the processor in very fast speeds and in large quantities. Most processors range between 1GHz and 3 GHz. Each GHz carries out 1 billion programming instructions per second. The crystal on the motherboard communicates to the processor how many GHz to carry out.


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Because of the great power it takes for the processor to carry out such fast calculations the processor can quickly heat up. For this reason it is found underneath a fan which makes sure that it does not overheat while carrying out instructions.





Random Access Memory

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  • Samsung
  • 2 Chips
    • 512 MB each
  • Located on the motherboard
  • 3 rows for RAM "chips"


The RAM in found on the motherboard in the middle of the computer in the form of integrated circuits and is the working memory of the computer. Random access memory (RAM) is a form of data storage which can be stored efficiently and accessed quickly. RAM is a short temporary storage and therefore once the computer is shut down, the RAM can no longer be accessed. The hard disk or external drives are used for more long term storage. There are places for extra RAM to be added on the motherboard. RAM comes in many sizes: bit, byte, kilobyte, megabyte, gigabyte, etc. The RAM storage in most electronics today is anywhere from 512MB to 8GB.


Hard Drive

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  • 40GB
  • Located below CD Drive


A hard disk drive is a device for storing information permanently. Retrieving data off of the hard drive takes a longer time than retrieving data from ram, but it is stored long term. It contains a metallic disk that is coated with magnetic material that connects to an actuator arm containing a magnetic head or spindle that can read and write data onto the surface of it. Many hard drives today contain about 1TB of storage.


CD/Floppy Drive

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  • The floppy disk drive is located above the CD drive in the corner of the computer above the hard drive

Floppy disk drives are used as forms of storage and exchange. According to [1] "A diskette, is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles. They are read and written by a floppy disk drive (FDD)." Motherboards are not compatible with most floppy disk drives nowadays.

CD Drives or Optical Disk Drives (ODD) use laser light and electromagnetic waves to read data that has been recorded on CD. It is attached to power supply cords and data transfer cords. Data transfer cables are thick cords that transfer data from the CD drive to the motherboard. The Power supply cables attach the CD drive to the power supply and are also attached to the motherboard. CD disks can back up small amounts of data as well in some cases when a computer has extra drives.


Ports

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According to [2]: “a port serves as an interface between the computer and other computers or peripheral devices. Physically, a port is a specialized outlet on a piece of equipment to which a plug or cable connects. Electronically, the several conductors making up the outlet provide a signal transfer between devices.”

  • Some ports that are used today are
    • Ethernet
    • IEEE 1394 interface
    • Parallel port
    • Serial port
    • USB drive
    • VGA connector

Power Supply

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  • Maximum output- 250 Watts
  • Located in the bottom right hand corner of the computer in a silver rectangular box with a fan on the side

According to [3] "A power supply unit (PSU) converts mains AC to low-voltage regulated DC power for the internal components of a computer. Modern personal computers universally use a switched-mode power supply. Some power supplies have a manual selector for input voltage, while others automatically adapt to the supply voltage." The power supply changes the energy from the wall socket which has a high voltage, to a lower voltage that the computer can use. The average watts a computer power can output is 500.


Links: Information on the Dell Optiplex GX280 [4] The PC demolition lab Computer Science 103 Wiki page with results of demolition class wiki